Composite structures are desirable in many industries for many applications. For example, aircraft, space, and land/sea vehicles employ a variety of curved and multiple-contoured surface structures in their fabrication. Composite materials such as fiberglass/resin are commonly used for these structures because, among other desirable attributes, composite materials have high strength-to-weight ratios. Because of the ever-increasing use of composite structures throughout industry, manufacturers are continually searching for better and more economical ways of forming composite structures.
In the forming of composite structures many manufacturing steps are performed. One such step that is usually required is a curing step. During the cure process, composites must be formed over tooling that restrains them. These tools are generally monolithic dies that are machined or cast from a solid block to conform to a specific surface shape and, therefore, cannot have their shape modified once created. Subsequent structures having different surface shapes, though similar, must have a new tool fabricated. This is a source of manufacturing time and expense. In addition, such monolithic dies are bulky, require much setup time at the form press prior to commencement of manufacturing, and utilize large amounts of storage space when not in a production mode. Present solutions attempting to resolve this problem have relied on metallic tooling surfaces that can be reconfigured. They utilize articulating sections, sliding pins, and other methods to change the shape of the tooling surface. These methods can leave dimples on the surface of the finished structure due to the nature of the reconfigurable elements. To alleviate the problem of dimpling, manufacturers employ many reconfigurable elements spaced very close to one another. However, the more hardware, the greater the expense and maintenance. Furthermore, structure size can be limited by these methods since scale-up can be cumbersome and expensive. And when large quantities of various contoured surface structures are required, each structure would require a separate rigid surface tool and would have to be durable enough for a production run. Lower cost tooling material options such as foam, which can be easily machined to create a family of tools, do not have the desired durability and each would require its own support base adding to the tool's cost.
The challenges in the field of materials construction have continued to increase with demands for more and better techniques having greater flexibility and adaptability. Therefore, a need has arisen for a new apparatus and method for constructing a composite structure.